Is there correlation between larger egg size and final bird weight

[For my girl]

I have two hens that lay gigantic eggs - 22 and one was 23 grams. The rest of mine are 14 to 16g. Instead of my normal 70% hatch rate I only get about 20% from those - and the chicks don't seem to be or to get any larger than the others. I am trying to hatch all of them though - because they might lay larger eggs.

 

[DK newbie]

Have you tried to open some of their largest eggs? The low hatch rate might be because many of the eggs are double yolkers..

 

[For my girl]

I open any that don't hatch to try to figure out why. I had 9 of the huge ones due to hatch yesterday. My others all hatch on time or early - but the really big ones are always late. I candled some last night and pulled 3 out. Two didn't even seem fertilized, and the 3rd must have given up within a day or two. I had one hatched overnight, and expect to get maybe one more. I haven't noticed any double yolks - they just seem to never start or to give up very early on. I normally candle at about 10 days, and again when going into lockdown - but I always keep the huge ones unless they are really obvious.

 

[Sara L]

How do you tell it's a double yolker without opening it? Is there a visible difference when candling? I've had a few really large eggs but was afraid to incubate them because I couldn't tell if they were double or single yolks.

 

[DK newbie]

Some say they can see the two yolkes when candling. I haven't tried.

 

[Russian Blue]

To the OP, SimonGrow, or any others: Do you have any follow up on your experimentation?

I'm currently selecting my largest birds (male and female) for a breeding group with the intent of producing larger offspring. My premise is that larger birds will equate to larger eggs. Once I have enough breeding stock, then I will select only the larger eggs from the largest birds.

I'm curious about the experimentation that others have done in the attempt to produce a larger egg. I love my coturnix quail, but if only their eggs were a little larger...

 

[Erkenstein]

Tatanka calls for culling out any birds that lay less than a 14-gram egg every day. Generally speaking, larger birds will lay larger eggs, although I have a jumbo that lays a regular-sized egg. To find her and cull her, I'd have to put hens in separate cages to figure it out, but I just don't incubate those eggs so same difference and she gets to live her life.

I'm working on upping the size of my birds over time by hatching out the larger eggs only. When I first started, I hatched out anything, but it's hard to butcher a bird that barely fills your hand and the tiny eggs aren't worth it. Now I only incubate jumbo eggs or standard eggs that are minimum 11 grams. I still get a few runty ones (usually females ), but they don't get to become breeders.

Small birds that lay giant eggs would get pruned out through prolapse and other health issues, and giant eggs generally don't have good fertility. Also, jumbo birds have more leg and foot issues. Nature tends to favor efficiency and not extremes. My eventual goal for my flock is consistent 14-gram+ eggs so at least it's 4:1 to chicken eggs.